Influence of Fibres on Concrete

Abstract

Concrete is the most widely used construction material, but its compressive strength can be limited by its brittle nature and susceptibility to cracking. This study investigates the effects of hybrid fiber reinforcement on the compressive strength of concrete by incorporating different types of fibers, such as steel, polypropylene, and glass, in varying proportions. A comparative analysis was conducted to assess the influence of hybrid fibers on strength development over time. Experimental results indicate that hybrid fiber-reinforced concrete (HFRC) exhibits significantly higher compressive strength compared to conventional concrete. The synergistic effect of multiple fiber types enhances load distribution and resistance to failure under cmpressive loads. This research highlights the potential of HFRC for high-performance structural applications, recommending further studies on optimizing fiber proportions for maximum compressive strength

Introduction

I. Introduction

Concrete is widely used for its strength, durability, and affordability, but it is brittle and prone to cracking under high loads. Fiber reinforcement, especially Hybrid Fiber-Reinforced Concrete (HFRC), improves these weaknesses. HFRC combines fibers like steel, polypropylene, and glass to enhance strength, crack resistance, and ductility. This study focuses on analyzing how different hybrid fiber combinations affect the compressive strength of M25 and M30 concrete grades.

II. Methodology

• Concrete Mixes: M25 and M30 grades were used with OPC, fine/coarse aggregates, and water.

• Specimens: Standard 150 mm cubes were cast and tested after 3, 7, and 28 days of curing.

• Fibers Used:

  • Glass fibers: 0.33%, 0.67%, 1%

  • Steel fibers: Hooked and plain, each at 0.2%, 0.4%, 0.7%

  • Polypropylene fibers: Macro and micro, each at 0.2%, 0.4%, 0.6%

• Hybrid combinations (e.g., steel + polypropylene + glass) were tested at 1% total volume.

III. Results & Discussion

Control Mix (Without Fibers):

• M25 28-day strength: 31.86 MPa

• M30 28-day strength: 38.27 MPa

Single Fiber Results:

• All fiber additions improved compressive strength over control.

• Steel fibers (0.7%) yielded highest strength among singles: ~39.22 MPa

• Glass fibers (1%) also performed well: ~38.97 MPa

• Polypropylene fibers showed moderate strength increases (around 17–20% improvement).

• Best cost-effective single fiber: Steel plain (0.2%) — 38.31 MPa at ?5,916/m³

Hybrid Fiber Results:

• Best overall strength: 40.16 MPa from the mix:
  Steel plain (0.25%) + Steel hooked (0.25%) + Macro PP (0.25%) + Micro PP (0.25%)

• Most cost-effective hybrid: Macro PP + Glass fiber
  Balanced compressive strength (~38.17 MPa) and moderate cost

• Most expensive:
  Steel hooked (0.5%) + Glass fiber (0.5%) at ?10,776.69/m³

Strength-to-Cost Ratio:

• Top performer:
  Steel hooked fiber (0.2%)—high strength gain with excellent cost-efficiency.

• Economical Hybrid:
  Macro Polypropylene + Glass fiber—great balance of performance and cost.

IV. Key Insights

• Hybrid fibers outperform single fibers in compressive strength.

• Cost increases with fiber complexity and content, especially steel and glass.

• Optimized blends like steel + polypropylene offer the best mix of strength and affordability.

• The choice of fiber should depend on application requirements and budget constraints.

Conclusion

Based on the result of test performed on the concrete specimen following conclusion can be drawn: 1) Hybrid fiber-reinforced concrete (HFRC) demonstrated a noticeable increase in compressive strength compared to conventional concrete, particularly at 28 days of curing. 2) The combination of steel hooked, steel plain, polypropylene (macro and micro), and glass fibers in optimal proportions led to improved strength performance due to the complementary behavior of each fiber type. 3) The best-performing hybrid mix—steel plain (0.25%) + steel hooked (0.25%) + polypropylene macro (0.25%) + polypropylene micro (0.25%)—achieved a maximum increase in compressive strength at 28 days over the control mix. 4) It was found that by using hybrid fibers, it is possible to achieve the compressive strength of M30 grade from an M25 grade base mix, however the cost reduction was not possible, on the contrary to some cases the cost was approximately double. 5) HFRC provides a sustainable construction solution, particularly by incorporating polypropylene and glass fibers, which can be derived from recycled or industrial waste materials. 6) Though hybrid fiber mixes are relatively costlier, they are suitable for applications where non cracking section and durability are essential. These include structures like water tanks where crack resistance is important, and industrial floors or workshop surfaces that require high abrasion resistance. In such cases, the performance benefits of hybrid fibers can justify the additional cost. 7) Despite improved strength, careful selection of fiber types and dosages is essential, as excessive or poorly balanced fiber content negatively impact cost.

References

[1] G.S.Sudhikumar, K.B.Prakash, M.V.SeshagiriRao (2014) Effect of Aspect Ratio of Fibres on the Strength Characteristics of Slurry Infiltrated fibrous FerrocementInternational Journal of Structural and Civil Engineering ResearchVol.3,No. 2 May 2014 [2] KomalChawla (2013) Studies Of Glass Fiber Reinforced Concrete Composites International Journal of Structural and Civil Engineering Research Vol. 2, No. 3, August [3] H S Jadhav and M D Koli (2013) Flexural Behavior Of Hybrid Fiber Reinforced Concrete Beams International Journal of Structural and Civil EngineeringResearchVol. 2, No. 3, August [4] N.VenkataRamana, U.RaghuBabu and E.ArunaKanthi (2021) Performance of Polyester And Polypropylene Fibres In Concrete International Journal of Scientific & Engineering ResearchVolume 7, Issue 4, April [5] Rajeev Chandak, R K Yadav and KanhaiyaLal Thakur (2014) A Study of Strength of Steel Fiber Reinforced Concrete With Fly Ash International Journal of Structural and Civil Engineering Research Vol. 3, No. 1, February [6] G. Murali, A. S. Santhi and G. Mohan Ganesh (2014) Effect of Crimped and Hooked End Steel Fibres on the Impact Resistance of Concrete Journal of Applied Science and Engineering, Vol. 17, No. 3, pp. 259266S [7] Mohd. GulfamPathan Ajay Swarup (2017) A Review on Steel Fiber Reinforced Concrete International Journal of Advance Research in Science and Engineering Volume NO.6, Special Issue No (01), December [8] Archana P, Ashwini N Nayak, Sanjana R Nayak, HarshitaVaddar (2017) Study of Strength of Polypropylene Fiber Reinforced Concrete International Journal of Engineering Research & Technology Vol. 6 Issue 06, June [9] SüleymanKamil Ak?n SadrettinSanc?oglu , SaruhanKartal , Ahmad Javid Zia, Abdullah Müsevito? glu , AbdulkerimIlgün Macro and micro polypropylene fiber effect on reinforced concrete beams with insufficient lap splice length Case Studies in Construction Materials [10] IS 10262:2019 - Concrete Mix Proportioning - Guidelines. [11] IS 12269: 1987 Specifications for 53 Grade of Ordinary Portland cement. [12] IS 2386 (Part III): 1963 Methods of Test For Aggregates For Concrete [13] IS 383:1970- Specification For Coarse And Fine Aggregates From Natural Sources For Concrete.

Copyright

Copyright © 2025 Sanket J Agham, Yash R Deore, Tanmay Metangale, Prerna Sharma, Dr. S. N. Khante. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.